Recovery of wind energy has been known for thousands of years. To utilize wind power for generation of electric current has been known since the invention of the electrical generator.
However, wind power has had difficulties successfully competing economically with other energy sources for electrical energy production. The utilization of the wind power for this has for long been limited to local energy supply and test plants. Even if commercial production of wind power-based electrical energy to the mains has developed considerably during the recent decades, the share thereof of the total electrical energy production is still very marginal.
In view of the great quantity of energy that potentially is available in the wind power and in view of different disadvantages associated with electrical energy production from other types of energy sources, it is important to create opportunities for an increased quantity of commercially competitive production of electrical energy based on wind power.
The predominant technique in generation of electrical energy from wind-power units has been based on units where the wind turbine has a horizontal axis. Different types of wind turbines having vertical axis have also been proposed. Among these, Savonius rotor, Darrerius rotor and H-rotor may be mentioned. As an example of the latter kind of rotors for wind power, reference is made to U.S. Pat. No. 6,320,273 and WO 03/058059.
In order to enable a wind-power unit to generate electrical energy at competitive prices, it is important to optimize each component 5, both from a technical and an economic point of view.
The present invention has as an object to provide such an optimization as regards the foundation on which the wind-power unit rests and the co-operation of the foundation with adjacent components.